One of the firearms taken in the burglary was on loan to the museum, said Wayne Motts, chief executive officer of the museum. The factory engraved Henry repeating rifle that had been presented to Secretary of War Simon Cameron was owned by a "third party," but Motts declined to further identify the owner.

The other stolen guns, two Colt revolvers that were purported to have been presented by Samuel Colt to Cameron in 1861, were owned by the city of Harrisburg. The city paid six-figures for the set of revolvers in 1996, according to a city official. The set was stolen along with its original wooden box, which also contained bullet molds.

The stolen guns, which are still functional, were displayed together in a case that was broken, said Police Capt. Gabriel Olivera. No other display cases were damaged, he said. Olivera said police initially were told the guns weren't part of the NRA exhibit, but they later learned that the guns were part of the Guns and Lace exhibit. The exhibit drew protesters last week.

Harrisburg police and Motts on Wednesday released additional information about the burglary along with photos of the stolen items during an afternoon news conference.

Olivera said the investigation had determined that the break-in occurred just after 6 a.m. Sunday. Video surveillance recorded the image of a lone male suspect, he said.

The video did not capture a recognizable image of the suspect, but police are continuing to work with the video, he said.

The museum's alarm system did not function properly because police were not notified until 12:40 p.m. Sunday, but museum officials would not say what went wrong.

The alarm company is preparing a report for museum officials evaluating the system, Motts said.

"Pending this report and its review, I'm not going to make any more comments related to the security system," Motts said. "The primary interest of the museum is the recovery of these three historic firearms. These are treasures of the American Civil War, related to one of the most prominent statesmen of the era."

Olivera said the security system had been fully reviewed and "everything is currently functioning." He said police were working with museum officials to identify other security enhancements.

Police on Wednesday confirmed that the burglar entered and exited the building through a broken ground-floor window, just to the left of the museum's front doors.

The loss of the rifle will be handled through the insurance carrier of the gun owner. The loss of the revolvers will be handled by the city's insurance coverage, Motts said. The revolvers had been displayed since the museum's opening in 2001.

Because of the ongoing conversation with insurance companies, Motts said he could not discuss the possible value of the guns.

Anyone who saw a vehicle entering the leaving the museum in Reservoir Park Sunday morning around 6 a.m. to 7 a.m. should call police, Olivera said. He also asked for residents to submit video surveillance they may have if it covers any portion of the park.

Police provided the following detailed descriptions of the guns:

The revolvers were a 44-caliber Army revolver, serial number, 11708, and a .36-caliber Navy revolver, serial 1825. They were contained in wooden case with a .44-caliber bullet mold, .36-caliber bullet mold, and a round tin container of 250 Eley Bros metal lined caps for Colt revolvers.

The rifle was an M1860 factory engraved Henry repeating rifle with "Cameron" on the receiver. The gun was made by the New Haven Arms Company, serial number 115.

UPDATE: This article was updated to add that the city paid six-figures for the revolvers.